Burdock Aglycone Pharmacokinetic Studies

Arctigenin has great value to be developed into a new medicine for its obviously anti-virus, anti-cancer, calcium antagonist action and PAF(platelet activating factor) antagonist activity. The pharmacokinetics study of Arctigenin is an important base for its new medicine developing. In this study, Arctigenin, the active ingredients in Fructus Arctii were prepared by chemical and chromatographic methods.A method was established for the determination of Arctigenin in biological-samples by HPLC in this paper. The calibration curve in plasma was liner in the range from 1. 916X10-1-4. 79X10-2ug with r=0. 9993, and the detection limit of this method was 9. 58Xl(Tu g. The extraction recoveries of all samples were over 70%, the relative standard deviations for within-day and between-day were below 8%. The methodological test indicated that the method was simple and good enough to be used in pharmacokinetic study of Arctigenin samples in biological samples.The absorption of Arctigenin through mice gastro-intestinal tract was studied in this report. The result indicated that Arctigenin was relatively stable in gastro-intestinal tract of mices and the absorption fit in first-order absorption with absorptive rate constant Ka=0. 642h-1 and absorptive half life T1/2=l.1h.The pharmacokinetics, bioavailability and excretion of Arctigenin were reported in this paper. The result showed that the concentration-time curves of Arctigenin after iv of 6,8, l0mg/kg to rabbits fit in a one-compartment model and the elimination of arctigenin from plasma was in according with linear kinetics. The concentration-time curve of Arctigenin fit in a one-compartment model after iv to rabbits with t1/2(ke)=52. 2min, Ke(l/min)=0. 01329, AUC=205. 66782. The concentration-time curve of Arctigenin after i. g into rabbits fits in one-compartment model with one order absorption. Ka=l. 4584 (1/h), Ke=0. 8888 (1/h), t1/2(Ka)=0. 48h, t1/2(Ke)=0. 78h, T(peak)=l. 56h. The absolute bioavailability of Arctigenin after i. g to rabbits is 9.5%. The 24h accumulated excreted amount from urine after i. g was 0. 423% and most amount of Arctgenin was excreted within 18h after i. g. The 24h accumulated excreted amount from feces after ig was 0. 11%.Arctigenin distribution in rats was studied and the result indicated that concentration of Arctigenin was the higher in liver and lung, followed by heart, spleen and kidney. Arctigenin was not found in brain tissues and this indicated that Arctigenin could not pass blood-brain barrier. The average plasma-protein binding percentage is 78.3% in rat.